Bioinspired figure-ground discrimination via visual motion smoothing
Fig 6
Effects of the receptive field size and stimulus parameters on figure-ground discrimination.
Unless specified below, the receptive field size of the lobula units on the EMD array was set as 14° × 14°, and a moving bar (25° width; 80% contrast; 2.6° dot resolution; 66°/sec speed) with a stationary background was used as the stimulus. The F-measures were averaged across the input frames (with the initial 50 frames excluded as transient frames) at the output stage of the Ir module. (A-B) Effect of the receptive field size on the averaged F-measure under different stimulus conditions. In panel (A), three dot resolutions, as specified at the top of each space-time plot, were tested: 2.6° (squares), 7.9° (triangles), and 13.2° (circles). In panel (B), three bar widths, as specified at the top, were tested: 5° (triangles), 25° (squares), and 45° (circles). (C-D) Effects of the stimulus velocity (C) and contrast (D) on the averaged F-measure. In panel (C), the background was not stationary but rather moving at −132°/sec, and the bar’s velocity was varied as specified along the abscissa axis.